Coffee producers have endeavored for years to produce an instant coffee whose taste could compare favorably with the taste of coffee brewed from quality roast and ground coffee beans. Despite numerous advertising campaigns to promote various brands of instant coffees, there is still no instant coffee on the market which can compare tastewise with coffee brewed fresh from quality roast and ground coffee beans.
The main reason for the difference in taste between fresh brewed coffee and instant coffee is the presence of aromatic compounds in the former. Instant coffees are as a rule less flavorful than ground roast coffees because the processes used to produce the instants nearly always drive off the volatilized aromatics.
Coffee aromatics are not found in nature. They are a product of the destructive distillation occurring in the roasting process. The quantity of aromatics produced is greater when high quality green coffee beans are roasted. Arabica coffee beans are usually an example of high quality coffee beans. At most, the aromatics are present in the roast beans to about 450 parts per million. It is difficult to retain the aromatics in the roasted coffee for other than a short time unless conditions are introduced into the processing and packaging operations which favor their extended longevity.